basic opencast matterhorn integration

[ppettit]

@androidwiltron said:

"get scheduled for each capture agent from mhorn ICal endpoint, parse and display the list of upcoming events for a defined time threshold.
useful to visually determine if CA is recording when it should be"

I replied:

"sounds good, we are not using scheduling though so would probably not have the time to work on it ourselves (but would accept merge requests 😉).

there is already a tab for controls on the room page as we have a partially implemented repository tab so maybe adding a schedule tab would be cool?"